According to me, it is always useful to use keywords in the URL. Using keyword in the URL will help your site get the first preference in the search engines. Google gives great value to URL carrying keywords. If your keyword is unique , and it is there in your page URL, Google will detect your page.
One of the many benefits of having the primary keyword in the URL is that even if some other websites link to the website using only its URL, the site will enjoy the advantage of the keyword as its anchor text.